Valve assembly



Dec. 18, 1962 J. w. LOGAN, JR., ET AL 3,068,900

VALVE ASSEMBLY 2 Sheets-Sheet 1 Original Filed'June 26, 1959 .Snwfmll d ,NQ mfvw. QR N smh M mpw E@ mw NS WJB NWN 0S 1 a2 WM V W x f 3 @N wm m Nm w if@ WH EN Sw Mw /w/MM/,U/N/ mE MW N wm.\ mw. NN N mm\ Q SNN E mw ws m SQ www n QS@ SN NSN i. www SS QNN wN @NN A s, SN Ww QN @H573 TWOKIVEY Dec. 18, 1962 J. w. LOGAN, JR., ET AL 3,068,900

VALVE ASSEMBLY 2 Sheets-Sheet 2 Original Filed June 26, 1959 um am NS N NSN N JNVENToRs' an J2' md @fo/212 W Log 12a/25m J .Bas/z. U .n/QJ. mima Ammanyff ite State Original application June 26, 1959, Ser. No. 823,136, now Patent No. 3,004,523, dated ct. 17, 196i. Divided and this application June 23, 1960, Ser. No. 38,367

6 Claims. (Ci. 137-623) Our invention relates to railway traic controlling apparatus, and particularly to a valve assembly for use in connection with a railway switch machine of the type operated by lluid under pressure.

The present application is a division of our copending application for Letters Patent of the United States, Serial No. 823,136, tiled on lune 26, 1959, for Railway Tratlic Controlling Apparatus, having issued on October 17, 1961 as Patent No. 3,004,528.

Railway switch machines embodying our invention are especially suitable for use in a railway classification yard to provide means for controlling track switches which route railway cars into selected turnout tracks leading to a number of classification tracks in the yard. The switch machines used in such an installation are respectively located normally a predetermined distance beyond the exit end of a car retarder mechanism employed for controlling the speed `of the cars. ln such a system, a track circuit, conveniently termed a detector track circuit, is connected in the control circuit of each switch machine and opens the `control circuit thereof when the track circuit is occupied to prevent the respective switch from reversing position during movement of a car over the switch. The distance between two successive humped cars routed over the same switch is preferably kept as 10W as possible in order to achieve a high rate of humping. To a large extentlthis distance is determined by the length of the detector track circuit with the space allowed between cars becoming smaller as the track circuit length is reduced. For more economical operation of the yard, and to avoid complex problems which have been found to arise during installation of the car retarder mechanisms, it is advantageous to keep the detector track circuit entirely outside the car retarder area and, in one classilication yard system contemplated, the entrance to the detector track circuit is located beyond the exit end of the car retarder mechanism. By thus placing the track circuit entrance at a point beyond the car retarder mechanism, the length available for the detector track circuit is shortened, and the spacing required between successive cars is minimized a corresponding extent.

The arrangement whereby the length of the detector track circuit is reduced allows satisfactory operation; however, by reducing the track circuit length/a `second car which is traveling at a relatively high speed and simultaneously is closely spaced from a leading car routed over the same switch may enter the detector track circuit before the switch reverses position, thereby continuing to lock the switch in the same position and possibly causing the second car to be misrouted. To compensate for the reduction in the length of the track circuit and the corresponding reduction in the allowable spacing between cars, it is expedient to provide a switch operating mechanism capable of rapid operation so as to ensure the correct classiiication of cars.

One object, therefore, of our invention is to provide a fast direct Vacting railway switch machine whose speed of operation is such that the amount of time required to complete a switching movement in response to a control signal is appreciably reduced.

' Another object of our invention is to provide a direct ice acting railway switch machine which ensures rapid operation of the switch or mechanism to be controlled from its one position to its other position.

Still another object of our invention is the provision in a railway switch machine of an improved electromagnetically-operated Valve which is designed for convenient installation and removal for inspection, maintenance and the like.

Yet another object of our invention is to provide a valve arrangement for use in connection with a railway switch machine, which valve arrangement is effective to materially reduce the amount of time required for per- -formin-g field or shop overhauls `or other maintenance work.

Another object yol" our invention is the provision in a railway switch machine of an improved electromagneticallyoperated valve for controlling tluid under pressure, means normally being provided to enclose the valve within :said machine, but which means can readily be removed to permit removal of the valve from the machine.

A general object ot our invention is to provide a railway switch machine of the type described which allows field emergency repairs of essential parts without necessitating removal of the machine from its location in the track.

Other objects and characteristic features of'our invention will become apparent as the description proceeds.

To attain the aforementioned objects of our invention we provide a conventional railway tratc controlling device, fluid pressure-actuated motor apparatus for controlling the device, and a spool-type slide valve arranged to control the admission of fluid under pressure from a suitable uid pressure source to one or the other side of the motor piston. Two valve structures, each comprising cooperating pin and magnet valves reciprocably movable in a suitable bushing and operable by an electromagnet in a conventional manner, are provided for controlling the supply of fluid under pressure to the slide valve. By means of our invention, removal and replacement of the pin and magnet valves in the eld is permitted without disturbance of the motor apparatus from its location.

We shall describe one form of apparatus embodying our invention, and shall then point out the novel features thereof in claims.

in the accompanying drawings:

FIG. l is a plan view partially in section showing a railway switch machine embodying our invention operatively connected with a railway switch.

FG.` 2 is an elevational view of the switch machine shown in FIG. l.

' FIG. 3 is a cross-sectioned view taken substantially along iine lll-lll of FIG. 2 showing, to better advantage, the slide valve incorporated in the railway switch machine embodying our invention;

FG. 4 is an enlarged view, partly in section, with certain of the parts removed, of the improved electromagnetically-operated valve structure embodying our invention.

Similar reference characters refer to similar parts in each of the several views.

Referring to FIG. 1 of the drawings, the reference character A designates a railway traiic controlling device,'here shown as a railway switch. The switch is operated by a fluid pressure-actuated motor B, which motor, as here shown, comprises a cylinder 10 and a reciprocable piston 12 operable therein. Fluid under pressure, usually compressedair, is at times applied to one end or the other oi' cylinder it] through passages 14 and 16 from a suitable source to be described. Secured to piston 12 at its one end is a piston rod 18 slidably mounted in suitable packing rings and 21, and operatively connected at its other end to switch A for moving switch A between normal and reverse positions.

As seen in FIGS. l and 2, cylinder 1i) of motor B is connected by means of bolts 22 with a cylinder head 24 provided with three uid passages 26, 28 and 39. The passage 26 is connected by means of a fluid passage, not shown, internally extending from passage 26 through the cylinder head to a pipe 32 (FIG. 2). The pipe 32 is connected to a suitable source of fluid under pressure, from which source the huid under pressure for operating motor B is taken, and in a manner to be described in detail hereinafter. Passages 28 and 3G are directly connected, respectively, with passages 14 and 16 of motor B.

The passages 28 and 36 of cylinder head 22 are arranged to be opened and closed to iluid under pressure by a valve device 33, the housing 34 of which is secured directly to cylinder head 24 by means of bolts 35 (FIG. 2).

The valve device 33 is of the pneumatically-operated type, and is preferably of the type disclosed and claimed in Letters Patent of the United States No. 2,747,611, issued May 29, 1956 to Ellis E. Hewitt. This valve device, as shown in FIGS. 1 and 2, and particularly as shown in FIG. 3, comprises a plurality of identical adjoining casing sections designated by reference numerals 36, 39, 4?, 42 and 44, each being provided with a chamber or bore, designated by the numerals 46, 48, 50, 52 and 54, respectively, the chambers all being aligned in coaxial relation with each other.

The casing sections 36, 38, 40, 42 and 44 are provided with screw-threaded ports or pipe-connecting bores 56, 5S, 60, 62 and 64, respectively, which connect chambers 46, 48, 5t), 52 and 54, respectively, to an external surface of the respective casing section.

A spool-type slide valve 66 extends coaxially through the several chambers 46, `48, 50, 52 and 54, and through a pair of cap portions 55 and 57. The valve 66 is provided with end portions 66a and 66h which project into cylindrical end caps 68 and 70, respectively, which end caps, cap portions, and casing sections are secured in any conventional manner herein not shown in abutting contact with each other. The end caps `68 and 70 are each formed interiorly with a concentric bore or charnber 76 and terminate, at one end of their respective bores 76, in screw-threaded ports '78 and 80, respectively. The screw-threaded portions 78 and 80 are shown connected with suitable pipe ttings 82 and 84, and the connections with the corresponding opposite ends of pipe littings 82 and 84 will be described as the specication proceeds. Respectively located within bores 76 of end caps 68 and 70 for sliding movement therein are two pistons 86 and 83 lixedly attached, respectively, to the end portions 66a and 66k of valve 66 by any suitable means such as, for example, by passing a cottered pin or roll pin 89 through aligned holes provided in the piston and the corresponding ends, as herein shown. The lower position of valve 66, as viewed in FIG. 3, is defined by the engagement of one side 88a of piston 88 with a surface 57a of cap portion 57, in which position a face 86a of the other piston 86 substantially abuts against the bottom of the bore 76 in end cap 68. Similarly, the upper position of valve 66, as seen in FIG. 3, is deiined by engagement of one side 86b of piston 86 with a surface 55a of cap portion 55, in which position a face 88b of the other piston 88 will substantially abut against the bottom of bore 76 in the other end cap 70. It will be understood, of course, that when the railway switch machine embodying our invention is installed adjacent a trackway for operation, valve device 33 and, consequently, valve 66 are disposed in a horizontal plane.

The valve 66 comprises four land portions 90, 92, 94,

and 96 disposed for sliding and sealing contact in resilient O-rings 98 which are located between adjoining casing sections, and which are also located between cap portions 55 and 57 and the two outer casing sections 36 and 44 adjacent thereto, respectively. Land portions 9i), 92, 94, and 96 are connected by reduced portions or grooves 100. Land portions 92 and `94- are of such length that when valve 66 is operated to its lower position, as described hereinabove, land portion 92 remains disposed in an interfering position between casing sections 36 and 38 for closing communication between chambers 46 and 48. At the same time, land portion 92 opens communication between chambers 48 and 56. Land portion 94 meantime is moved to a position to open communication between chambers 52 and 54, and to close communication between chambers Sti and 52. When valve `66 is operated to its upper position, as described hereinabove, land portion 92 will move from its previous position between casing sections 36 and 38 and thereby now open communication between chambers 46 and 48 while, at the same time, moving to an interfering position in which communication is closed between chambers 48 and 50. Land portion 94 will simultaneously move to a position to open communication between chambers 5t! and 52, and to close communication between chambers 52 and 54. Hence, it can be seen that operating the valve 66 to its other end position closes the chambers that were open and opens the chambers that were closed. Due to the sliding friction between the land portions of valve 66 and the `O-rings 98, valve 66 remains, when operated, in its upper and lower positions according as a lluid pressure torce, preferably compressed air, acts, in a manner to be described in detail hereinafter, against piston 86 or 88, respectively.

The screw-threaded ports 56 and 64 of valve device 33 are merely open to atmosphere; ports 58 and 62 communicate respectively with passages 28 and 30 of cylinder head 24 by means of grommeted sleeves 102 which extend inside one end of threaded adapters 104, the adapters 104 in turn being screwed at their other end into ports S8 and 62; and port 60 communicates with passage 26 of cylinder head '24 by means of a similar sleeve and adapter. Thus, when valve 66 occupies the position in which it is shown in FIG. 3, uid communication is established between passage 26 of cylinder head 24, port 60, chambers 50 and 48, and port 58 of valve device 33, and passage 28 of cylinder head 24 and passage 14 of motor B to admit fluid under pressure to the left-hand side of piston 12. At the same time, the right-hand side of piston 12 is directly connected with atmosphere through a fluid passageway including passage 16 of motor B, passage 36 of cylinder head 24, and port 62, chambers 52 and 54, and port 64 of valve device 33. It will be appreciated that by exposing directly to atmosphere that side of piston 12 opposite to the side to which Huid under pressure is applied each time a movement of switch A is elfected, piston 12 encounters no appreciable fluid pressure resistance as it moves between the ends of cylinder 1G of motor B, thereby greatly reducing the time required for movement of piston 12 to consequently reduce the time required to operate switch A from one to the other of its positions.

A control over the speed of switch A may be desired to slightly retard the movement of switch A immediately prior to the time a reverse movement of the switch has fully been completed to avoid slamming the switch to thus protect the points thereof from damage. Hence, a choke device (not shown) may be provided and screwed into ports 56 and 64 of valve device 33 to regulate the How of liuid under pressure from either side of piston 12 to atmosphere during movement of piston 12 in either direction of its stroke. The choke device may assume various forms well known in the art and may, for example, as herein contemplated, comprise a bored plug (not shown) screwed into the ports 56 and 64, with the diameter of the core in the plugs determining the rate of escape of duid under pressure to atmosphere from the chambers `46 and 54 of valve device 33.

In accordance with our invention, the admission of fluid under pressure to valve 66 is controlled by two identical valve structures, only one of which, herein designated 106, is illustrated, which valve structures are operated,

respectively, by identical electromagnets 108 and 110, one or the other `of which is energized according to the desired position of switch A. Inasmuch as the valve structures and their associated electromagnets are identical in operation and construction, we have chosen only to describe that valve structure and associated electromagnet which appears in the upper part of FIG. 1, which valve structure and a portion of the associated electromagnet we have for purposes of simplicity more clearly illustrated in FIG. 4.

Referring now to FIG. 4, the valve structure 106 is housed in a substantially cylindrical bushing 112 and includes detachably connected valves 114 and 116 which operate respectively as inlet and exhaust valves. The bushing 112 and the valves 1x14 and 116 when assembled together form a valve subassembly which can be regarded as a replaceable unit, as will be described hereinafter. Furthermore, it will be understood that in practice either one of the pair of valves 114 and 116 may serve as the inlet valve with the remaining one serving as the outlet valve depending upon the desired arrangement of the external connection to the ports controlled by the valves. The bushing 112 is mounted in an annular opening 118 provided in -a housing or enclosure member 120 formed integrally with cylinder head 24 at one end thereof and is movable laterally Within the opening for a purpose which will be made clear as the specification proceeds. The outer surface 112a of bushing 112 is provided with two spa-ced annular grooves in which O-rings 121 for sliding and fluid pressure sealing purposes are located. The bushing 112 is formed at one end with a longitudinal hole 112C, and is slightly reduced Ain diameter at its other end, which other end is provided with another longitudinal hole 112d in axial alignment with the hole 112C. The bases of holes 112e and 112d are communicably connected by an aperture 112e extending through an intermediate portion 112.]t of bushing 112, which aperture is considerably smaller in diameter than either hole 112C or 112d and concentric therewith. The aperture 112e is suitably proportioned to loosely receive a stem 122 having its one end connected to pin valve 114. The other end of stem 122 fits into a recess 116er provided centrally in valve 116. It

will be understood, however, that stem 122 may instead be provided on valve 116, and a recess for receiving the stem then be provided in valve 114. In either case, such an arrangement, whereby valves 114 and 116 are detachably connected to each other, permits the most trouble-V some parts of the switch machine embodying our invention to be independently examined and inspected when valves 114 and 116 are detached from each other, as will be described.

The valves 114 and 116, as shown in FIG. 4, are in their `respective normal positions, and cooperate respectively with valve seats 114a and 116b at the Opposite ends of laperture 112e such that when one valve is seated the other is unseated. Guided by the inner surface of hole 112d, and formed integrally with valve 116, is `a gen erally triangular shaped member 124 which allows air to pass along its sides and against a plane surface 124er of which a tapered armature stem 110er` of electromagnet 110 abuts.

Referring now specifically to FIG. l, the electromagnet 110 is of standard construction and comprises briey a hollow core 110b surrounded by -a winding 110e. An

armature 11011 cooperates with armature stem 11011, the armature being held in juxtaposition to the armature stem by a lock nut e. The core 110k is provided outside the main body of the electromagnet with a threaded extending portion 1101, one end of which is threadably connected with one end of housing to close one end of opening 118. The other end of opening 11S is closed by a cap nut orplug 126 screwed into housing 120. To bias valves 114 and 116 to their respective normal positions, a coil spring 128 contained in a cup 130 secured to cap nut 126 acts against an annular shoulder 132 on valve 114 in a direction to normally seat valve 114 and to unseat valve 116, substantially as shown in FIG. 4. When electromagnet 108 becomes energized, valves 114 and 116 are operated, in opposition to the bias of spring 128, to positions in which they become unseated and seated, respectively, as shown in FIG. 1.

In order to gain access to valves 114 and 116, cap When electromagnet 103 becomes energized valves 114 and a screw driver or similar conventional tool, not shown, is applied to a groove 112g (FIG. 4) provided on one end of bushing 112. To completely Withdrawn bushing 112 and the valves 114 and 116 mounted therein from within opening 118, a relatively light force is then applied to the screw driver, in a direction away from electromagnet 110; With such an arrangement, both valves 114 and 116 are immediately. accessible and when removed from the bushing they may be detached from each other, as previously mentioned. If the valves are found to be excessively Worn due to repeated operation, either valve may be restored to condition for service or replaced, or discarded at the end of a predetermined duration of active ervice. Such an arrangement obviously simplifies maintenance procedure to correspondingly reduce the cost of maintenance. Furthermore, removably mounting the bushing as embodied in our present invention enables the bushing, and the valves therein, as a unit, to be used to replace, for example, a defective unit, thus making it possible to conveniently correct any valve problem without detaching the electromagnet from housing 120.

The cap nut 126 closes a cavity 126e to which uid under pressure is constantly supplied by means of a pipe connection 134, best shown in FIG. 4, which may be coupled by any suitable means, not shown, to the source of fluid under pressure indicated in FIG. 2. The fluid under pressure for operating spool valve 66 is taken from this cavity and is intended to be applied through aperture 112e and a port 112k which extends through the intermediate portion 112f of bushing 112 to a transverse hole 120g bored in housing 120, the aperture 112e, port 112k, and hole 120a all being connected in direct fluid communication with each other. This hole 12011 receives one end of a pipe fitting 136, which pipe litting is clearly illustrated in FIG. 4, and at the upper part of FIG. 1. The other end ofthe pipe tting 136 is connected by means of a pipe or tubing 133 with one end of pipe fitting 84. It Will be recalled that pipe fitting 84 has its other end connected with the port 80 in end cap 70 of valve device 33. Moreover, a pipe fitting 140, shown in the lower part of FIG. 1 connecting with the other housing 120, is connected by a similar pipe or tubing 138, andV pipe fitting 82 with port 78 in end cap 68 at the other end of valve device 33. The housing 120 is further provided adjacent its other end with another transverse hole 120b continually connected with atmosphere. With valves 114 and 116 in their respective normal positions, iluid communication is established between hole 12011 and aperture 112e by means of holes 112i aligned with hole 120b and bored through the wall of bushing 112.

The fluid under pressure charging cavity 126g may tend to force bushing 112 deeper into opening 118. If the movement of bushing 112 in this direction is not arrested after a certain relatively small extent, the O-ring 121 nearest to the cap nut 126 may be displaced from its i present position to a position in which it becomes entangled in hole 120a in extension 120 and perhaps forced from its groove. To avoid the obvious consequent damage to the O-ring, bushing 112 is provided with a snap ring 142 (FIG. 4) which by its engagement with a flat inner surface 120C of housing 120, should lateral movement of the bushing become excessive, will limit movement of the bushing 112 into opening 11S. Moreover, the extent of movement of bushing 112 in response to an oppositely directed force, such as, for example, a force produced by the impact of Valve 116 against its seat, will be limited due to the other side of the snap ring acting against an inner surface 12611 of cap nut 126.

To secure electromagnet 110 firmly in place against the housing 120 of cylinder head 24, the extending portion 1101 of core lltb of the electromagnet 110 is provided with an adjustable lock nut 144. Initially, as extending portion 114)]c is screwed into opening 118, lock nut 144 is backed off to a position in which it abuts against a second lock nut 146, which lock nut 145 is also mounted on the extending portion 1101. Eventually, as the rotation of electromagnet 11i) is continued, lock nut 144 in its backedoil position strikes extension 120 and the rotation of electromagnet 110 is arrested. Before the electromagnet is rigidly locked against movement, adjustment of the armature stem 110a relative to member 124 will generally be required to ensure a suitable working relationship between valves 114 and 116 and their respective valve seats when they are operated. To accomplish this adjustment, lock nut 116 securing stem 110:2 to armature 110d is somewhat loosened and the armature stem is moved along its longitudinal axis until the valves occupy the position in which they are shown in FIG. 4, whereupon lock nut 110e is retightened. Should it be necessary, electromagnet 110 is thereupon rotated in a reverse direction until terminals 148 are in positions best suited for connection with lead-in wires not shown. Because of the reverse rotation of the electromagnet following establishment of the operative connection between the armature stem and the valve assembly, a relatively slight separation will tend to occur between the inner end of the armature stem and member 124. However, the abutment between the armature stem and member 124 will immediately be reestablished as the armature stem moves since the bushing 112, in response to the Huid under pressure at its one end in cavity 126g, will be moved axially toward core extension 110 as the electromagnet is backed off. That is, when the positions of the terminals 148 relative to the lead-in wires are adjusted, bushing 112 will travel linearly an extent proportional to the angular distance of the electromagnet during its reverse rotation and the armature stem adjustment will, therefore, remain unchanged. It will readily be appreciated that, by allowing the bushing to float within its enclosure, contact between the actuating member of the electromagnet and the valve assembly will be assured absolutely regardless of angular adjustment of the electromagnet. It will further be appreciated that this mounting arrangement, and the ability of the bushing to drift freely within the limits hereinabove described, provides a convenient means for gaining access to the coil terminals of the electromagnet with lead-in wires whose length, for instance, may be so short that connection to the coil terminals would otherwise be diflieult. After connection to terminals 14S of such lead-in wires, lock nut 144 is tightened against housing 120 to firmly lock the electromagnet in place.

The operation of this arrangement is as follows: When neither electromagnet is energized, valve 66 occupies one or the other of its operated positions according as uid under pressure was last admitted to either one or the other end of valve device 33, substantially as described hereinabove.

Assuming now that the electromagnet 11i) becomes energized, valve 114 is moved in a direction to become disengaged from seat 11451, and valve 116 simultaneously moves in the same direction to engage seat 116a and thereby close communication between aperture 112e and atmosphere. The opening of valve 114 admits fluid under pressure to aperture 112e and to the previously traced fluid path including pipe fitting 136, pipe 138, and pipe fitting 84 to port S0 of valve device 33. The admis sion of fiuid under pressure to port of valve device 33 causes movement of valve 66 in such direction as to cause fluid under pressure to be admitted to passage 14 of motor B, as hereinabove explained. Piston 12 of motor B will thereupon move to the right, as viewed in FIG. 1.

Fluid under a relatively lower pressure and created at the right hand side of piston 12 by the sudden movement of piston 12 to its right will meantime pass to atmosphere, substantially as described hereinabove.

One `feature of the valve apparatus embodying our invention is that the electromagnetically-operated valves are accessible at all times for servicing or maintenance purposes. That is, it is possible with this construction to remove the cap nuts which enclose the valve structures within their respective housings merely by applying to the cap nuts a Istandard tool of the type generally carried by signal maintainers. It can be seen that once the cap nut is removed, the bushing and the valve structure mounted therein may be removed for immediate inspection, there being no fixed attachment between the valve structure and the armature stem of the electromagnet operatively associated with each valve structure. In addition, once the electromagnet is tixedly mounted for operation and its terminals connected to the energizing source, it can be seen that the novel approach to the problem of simplifying valve adjustment removes the doubt that variations from the initial valve adjustment will occur.

Although we have herein shown and described only one form of valve assembly embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. A valve arrangement comprising, in combination, a cylinder, an axially movable bushing disposed in said cylinder, a valve disposed in said bushing concentric therewith and movable relative to said bushing between a first position and a second position, an electromagnet having an axially movable rod-like member, said rod-like member disposed in alignment with said bushing and having its one end abutting against said valve for moving it, whereby when said electromagnet is energized said rod-like member is moved from a nonactuated position to an actuated position to move said valve from its first to its second position, and means for applying fluid under pressure to a preselected end of said cylinder, whereby said fluid pressure will force said bushing axially toward said rod-like member to automatically maintain the abutment between said rod-like member and said valve.

2. In combination, an enclosure member having a substantially cylindrical opening, an axially movable bushing disposed in and aligned longitudinally of said opening, a valve in said bushing mounted for axial movement relative to said bushing between a first position and a second position, said bushing provided with a port controlled by said valve, actuable valve operating means having an axially movable rod-like member operatively connected with said valve for moving it, whereby when said valve operating means is actuated said rod-like member is moved from a nonactuated position to an actuated position to move said valve from its first to its second position, and means for applying compressed air to said enclosure member to move said bushing in a direction toward said rod-like member, said bushing responding to said compressed air to hold said valve in operative connection with said rod-like member to permit immediate movement of said valve from its first to its second position in response to actuation of said valve operating means.

3. In a valve mounting arrangement, the combination comprising a mounting member provided with an opening extending longitudinally from one end to the other end of said mounting member, an axially movable bushing disposed in said opening and provided with at least one port, means for applying fluid under pressure to said mounting member at one end of said opening, valve means for controlling `fluid communication to said port concentrically arranged in said bushing and movable relative to said bushing between a biased first position and a second position, an electromagnet adjustably rotatably secured to Asaid mounting member at the other end of said opening and comprising a movable actuating member and electrical terminals adapted for Iconnection with a source of current, means in said electromagnet for positioning said actuating member relative to said valve means such that one end of said actuating member normally abuts against said valve means for moving it from its first to its second position when said electromagnet is energized, said electromagnet being rotated relative to said mounting member in a reverse direction when said abutment is established until said terminals occupy any angular position best suited for connection with said source, and said bushing responding to said fluid under pressure during said reverse rotation and moving toward said other end of said opening to maintain the abutment between said valve means and said actuating member and ensure movement of said valve means in response to movement of said actuating member.

4. In a valve assembly for an electromagnetically operated valve, the combination comprising a generally elongated housing having an opening extending longitudinally through said housing from end to end, said opening being screw-threaded at both ends, a bushing disposed in said opening and axially movable with respect to said housing, said bushing having a first aperture extending longitudinally from one end to the other end of said bushing and a second aperture extending from said first aperture at a point intermediate its ends to a preselected point on the periphery of said bushing, a pair of sealing gaskets on said bushing one located on each side of said preselected point for sliding and sealing engagement with the adjacent boundary surface of the opening, valve means operable between a nonactuated position and an actuated position adapted to cooperate with the ends of said first aperture and effective in its nonactuated position for controlling munication between said one end of said bushing and said second aperture and in its actuated position for controlling communication between said other end of said bushing and said second aperture, means for actuating said valve means from its nonactuated to its actuated position screwed into said housing at one end of said opening, cap means for closing the other end of said opening also screwed into said housing, and means on said cap means for biasing said valve means -to its nonactuated position.

5, In a valve assembly for a valve, the combination comprising a generally elongated housing provided with an opening extending from one end to the other end of said housing and being screw-threaded at both ends, a bushing disposed in said opening and having a first passageway extending therethrough concentric with the longitudinal axis of said bushing and a second passageway extending from said first passageway to the periphery of said bushing, sealing gaskets on said bushing one on each side of the peripheral opening of said second passageway, said gaskets disposed in sealing contact with the adjacent boundary surface of said opening but permitting sliding movement of said bushing relative to said housing, a first valve seat at one end of said first passageway and a second valve seat at its other end, a valve stem mounted in said first passageway and freely movable therein relative to said bushing, a first valve on one end of said stem adapted to cooperate with said first seat, a second valve adapted to cooperate with said second seat loosely mounted on theother end of said stern so as to be capable of being separated therefrom, said stem and said first and second valves being arranged such that when one of said valves is seated the other -is unseated, cap means screwed into said housing at one end of said opening adjacent to said first valve for closing said one end of said opening, means on said cap means acting against said first valve for biasing said first valve closed and said second valve open, means for actuating said first and second valves screwed into said housing at the other end of said opening and having a longitudinally movable actuating member disposed in abutting engagement with said second valve, whereby when said valve actuating means is actuated said first valve is opened and said second valve is closed in response to movement of said actuating member, the arrangement being such that when said cap means is un screwed from said housing said bushing including said first and second valves may readily be removed in endwise fashion from said housing, but that when only said valve actuating means is unscrewed only said second valve may be removed from said housing.

6. In a mounting arrangement for an electromagnet, the combination comprising a fixed mounting member having a plane surface at its one end and a screw-threaded hole normal to the plane surface thereof, said electromagnet comprising a main body and including a screwthreaded core extension, a lock nut adjustably mounted on said core extension, electrical terminals onthe main body of said electromagnet adapted for connection with a source of current, said core extension being screwed inwardly into said screw-threaded hole until said terminals are in an angular position-best suited for connection with said source, and said lock nut then being positioned to frictionally engage the plane surface of said mounting member -in a manner to removably mount said electro magnet to said mounting member.

References Cited in the file of this patent UNITED STATES PATENTS 2,204,808 McNeal June 18, 1940 2,658,523 Johnson Nov. 10, 1953 2,853,976 Gerwig et al Sept. 30, 1958 

